Windsurf ZUGFeRD Validator check_consistency

How to: Windsurf ZUGFeRD Validator check_consistency

client:Windsurf transport:streamable-http tool:check_consistency

Add ZUGFeRD Validator to Windsurf

01
Open ~/.codeium/windsurf/mcp_config.json and merge this in. Keep any servers already there.

{
  "mcpServers": {
    "validator": {
      "serverUrl": "https://api.zugferd-validator.de/mcp"
    }
  }
}

02
Save the file and restart Windsurf.
03
Ask for something check_consistency does. Windsurf lists the server's tools on connect and calls check_consistency itself — you do not invoke it by name.
04
If nothing happens, check the server is running and that ZUGFeRD Validator's identifier in your config matches the one above exactly.

Global only — Windsurf has no per-project MCP config. Refresh Cascade after saving. Windsurf docs

Set these first

ZUGFeRD Validator will not start until these are set, so check_consistency never becomes available.

ZUGFERD_API_KEY

Same tool, other clients

This list was read from the server itself, by connecting to it and calling tools/list on 24 September 2026. It is what the server actually exposes, not what its listing claims.

Mutating and Read-only are read off each tool's name, not its schema — a hint, not a guarantee. The registry stores tool names only; connect the server for its live schemas.

ZUGFeRD Validator MCP server